Live recombined vaccines injected with adjuvant

ABSTRACT

The recombinant live vaccine comprises a viral vector incorporating and expressing in vivo a heterologous nucleotide sequence, preferably a gene of a pathogenic agent, and at least one adjuvant compound chosen from the acrylic or methacrylic polymers and the copolymers of maleic anhydride and an alkenyl derivative. It is in particular a polymer of acrylic or methacrylic acid cross-linked with a polyalkenyl ether of a sugar or polyalcohol (carbomer), in particular cross-linked with an allyl sucrose or with allylpentaerythritol. It may also be a copolymer of maleic anhydride and ethylene cross-linked, for example, with divinyl ether.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the national phase filing of PCT/FR90/00453 filed inaccordance with 35 U.S.C. §371.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable

FIELD OF THE INVENTION

The present invention relates to an improvement to recombinant livevaccines integrating and expressing in vivo one or more heterologousgenes. It relates in particular to such adjuvant-containing vaccines, tothe use of particular adjuvant compounds for using such vaccines as wellas to vaccination methods relating thereto. Its subject is also a methodof preparing these vaccines.

BACKGROUND OF THE INVENTION

It is conventional to incorporate into inactivated or subunit vaccinesadjuvants intended to increase the immune response towards the antigenswhich these vaccines contain.

It has also been found to incorporate adjuvants into attenuated livevaccines when the attenuation of microorganisms leads to a reduction inthe immune response.

Recently, combined vaccinations against several pathogens using aninactivated vaccine for one valency and an attenuated live vaccine forthe other valency have also been proposed. It has thus been proposed toreconstitute the attenuated live vaccine, preserved in freeze-driedform, in the composition of an adjuvant-containing inactivated vaccine.The said composition acts as reconstitution vehicle for the livevaccine, without any adjuvant effect being sought for it.

EP-A-532 833 proposes a vaccine against horse rhinopneumonia, apathology caused by the equine herpesvirus (EHV). The vaccine is aninactivated and adjuvant-containing vaccine, grouping together theinactivated EHV-4 virus and EHV-1 virus, containing the adjuvantHavlogen®, based on a polyacrylic polymer.

As for most herpesviruses, there is currently no effective vaccineallowing rapid elimination of the virus after infection. The knownvaccines attempt to protect against the appearance of clinical signs. Ingeneral, the effect on viral excretion remains limited.

According to EP-A-532 833, the vaccine developed is thought to lead to adrop in viral excretion ranging from 79 to 93% (see results section).Eight control animals out of nine excreted virus after a challenge overan average of 1.4 days whereas the normal duration of excretion afterchallenge is usually greater than or equal to 5 days. This represents achallenge of low intensity which artificially increases the protectionof vaccinated horses compared with the controls. The reduction in viralexcretion is not therefore significant in this experiment.

Adjuvants of the carbomer type have also been used in inactivatedvirus-containing equine influenza vaccines (IEV).

Mumford et al (Epidemiol. Infect. (1994), 112, 421-437) recall that twoequine IEV vaccine doses are required to induce a transient humoralresponse and a weak protection against the virus in horses. The authorscompare the adjuvant effects of carbomer and of aluminium phosphate oninactivated vaccines in the presence or otherwise of tetanus toxoid. Inall cases, a low antibody titre measured by the SRH (single radialhaemolysis) technique with respect to the strains H7N7 and H3N8 isobtained after a first vaccination and a second and then thirdvaccination are necessary to see the appearance of stronger transientresponses.

U.S. Pat. No. 4,500,513 also presents vaccination trials against theequine influenza virus with an inactivated vaccine in the presence of acarbomer. The origin of the animals and their medical status is notindicated precisely and it appears that they are ground animals (column11, 2nd paragraph). The high antibody titres, measured by ahaemagglutination inhibition technique, indicate that the animals hadprobably already been infected with influenza and that the responseinduced after vaccination was of the booster type, and not of theprimary vaccination type.

Finally, Fort Dodge Solvay markets inactivated equine influenza vaccines(Duvaxyn® IE and IE-T plus) and an inactivated equine rhinopneumoniavaccine (Duvaxyn® EHV_(1,4)), in a carbomer adjuvant.

Commercial inactivated vaccines against equine influenza, containing theadjuvant aluminium hydroxide (for example Tetagripiffa®, Mérial, Lyons,France) are also known.

A large number of other adjuvants are used in the context ofconventional inactivated or subunit vaccines. There may be mentioned,for example, aluminium hydroxide, aluminium phosphate, Avridine®, DDA,monophosphoryl lipid A, Pluronic L121 and other block polymers, muramylpeptides, saponins, trehalose dimycolate, copolymers of maleic anhydrideand ethylene, copolymers of styrene and acrylic or methacrylic acid,polyphosphazene, oily emulsions and the like.

WO-A-94 16681 suggests supplementing a recombinant live vaccineexpressing a heterologous gene of an enveloped virus with an adjuvantvaccine composition in the form of a water-in-oil, oil-in-water orwater-in-oil-in-water emulsion.

Such a solution may however have a number of disadvantages.

In practice, the final user should have available, on the one hand, afreeze-dried active ingredient and, on the other hand, an alreadyconstituted emulsion which should make it possible to reconstitute thefreeze-dried active ingredient.

Lack of stability of the emulsion during storage could be detrimental tothe efficacy and safety of the reconstituted vaccine.

The activity of attenuated live microorganisms could be called intoquestion following their instability in the oily phase. This may inparticular be the case for viruses which may thereby lose theirviability.

Vaccines in emulsion can also pose problems of safety at the site ofinjection.

BRIEF SUMMARY OF THE INVENTION

The present invention is therefore given with the objective of providingnew vaccine compositions based on recombinant live vaccine expressing atleast one heterologous nucleotide sequence, especially a heterologousgene, containing an adjuvant which is capable of remarkably increasingthe immunity conferred relative to the same vaccine with no adjuvant andwhich is perfectly suitable for this type of vaccine.

The Applicant has found the carbomer class of compounds were capable ofacting as adjuvant under the required conditions for this type ofvaccine and this in unexpected proportions. Trials carried out on animalherpesviruses (EHV-1, Equine Herpesvirus) have shown that the supply ofcarbomer could reduce viral excretion during an experimental infection,in unexpected proportions. Other trials carried out on the equineinfluenza A virus have made it possible to obtain, surprisingly, inhorses, early and very high serological titres, better than thoseobtained with the best commercial vaccines.

The subject of the present invention is therefore a recombinant livevaccine comprising a viral vector incorporating and expressing in vivo aheterologous nucleotide sequence, preferably a gene for a pathogenicagent, and at least one adjuvant compound chosen from the polymers ofacrylic or methacrylic acid and the copolymers of maleic anhydride andalkenyl derivative.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in greater detail with the aid ofthe embodiments taken by way of non-limiting examples and referring tothe drawings.

FIG. 1 depicts the nucleotide sequence of the EIV HA gene of the EIVNewmarket 2/93 strain (SEQ ID NO: 1).

FIG. 2 depicts the nucleotide sequence of the feline herpesvirus-1(FHV-1) gc gene (SEQ ID NO: 2 FIG. 3 depicts a graph showing thevariation of viral excretion after experimental injection in horsesvaccinated with the aid of different vaccines against EHV. In FIG. 3, ▪represents vCP132 and water (A), ♦ represents vCP132 and carbomer (B), ▾represents a commercial vaccine (C) and □ represents a control (D).

The preferred compounds are the polymers of acrylic or methacrylic acidwhich are cross-linked, especially with polyalkenyl ethers of sugars orpolyalcohols. These compounds are known by the term carbomer(Pharmeuropa Vol. 8, No. 2, June 1996). Persons skilled in the art canalso refer to U.S. Pat. No. 2,909,462 (incorporated by reference) whichdescribes such acrylic polymers cross-linked with a polyhydroxylatedcompound having at least 3 hydroxyl groups, preferably not more than 8,the hydrogen atoms of at least three hydroxyls being replaced byunsaturated aliphatic radicals having at least 2 carbon atoms. Thepreferred radicals are those containing from 2 to 4 carbon atoms, e.g.vinyls, allyls and other ethylenically unsaturated groups. Theunsaturated radicals may themselves contain other substituents, such asmethyl. The products sold under the name Carbopol® (BF Goodrich, Ohio,USA) are particularly appropriate. They are cross-linked with an allylsucrose or with allyl pentaerythritol. Among them, there may bementioned Carbopol® 974P, 934P and 971P.

Among the copolymers of maleic anhydride and alkenyl derivative, thecopolymers EMA® (Monsanto) which are copolymers of maleic anhydride andethylene, linear or cross-linked, for example cross-linked with divinylether, are preferred. Reference may be made to J. Fields et al., Nature,186: 778-780, Jun. 4, 1960, incorporated by reference.

From the point of view of their structure, the polymers of acrylic ormethacrylic acid and the copolymers EMA® are preferably formed of basicunits of the following formula:

in which:

R₁ and R₂, which are identical or different, represent H or CH₃

x=0 or 1, preferably x=1

y=1 or 2, with x+y=2

For the copolymers EMA®, x=0 and y=2. For the carbomers, x=y=1.

The dissolution of these polymers in water leads to an acid solutionwhich will be neutralized, preferably to physiological pH, in order togive the adjuvant solution into which the vaccine itself will beincorporated. The carboxyl groups of the polymer are then partly in COO⁻form.

Preferably, a solution of adjuvant according to the invention,especially of carbomer, is prepared in distilled water, preferably inthe presence of sodium chloride, the solution obtained being at acidicpH. This stock solution is diluted by adding it to the required quantity(for obtaining the desired final concentration), or a substantial partthereof, of water charged with NaCl, preferably physiological saline(NaCl 9 g/l), all at once or in several portions with concomitant orsubsequent neutralization (pH 7.3 to 7.4), preferably with NaOH. Thissolution at physiological pH will be used as is to reconstitute thevaccine, especially stored in freeze-dried form.

The polymer concentration in the final vaccine composition will be 0.01%to 2% w/v, more particularly 0.06 to 1% w/v, preferably 0.1 to 0.6% w/v.

The invention proves particularly useful for vaccination against animalherpesviruses. The invention relates most particularly to the equineherpesvirus (EHV-1 and EHV-4 in particular), feline herpesvirus (FHV),canine herpesvirus (CHV), avian herpesvirus (Marek and ILTV), bovineherpesvirus (BHV) and porcine herpesvirus (PRV=Aujeszky's disease virusor pseudorabies virus).

The subject of the invention is therefore recombinant live vaccinescomprising at least one viral vector incorporating and expressing atleast one gene of such a herpesvirus and at least one adjuvant inaccordance with the invention.

By way of example, persons skilled in the art may refer to WO-A-92 15672(incorporated by reference), which describes the production ofexpression vectors based on poxviruses capable of expressing such genes.There will be found for example a canarypox expressing the gB, gC and gDgenes of EHV-1 (vCP132), which is also applicable to EHV-4, a vacciniavirus expressing these same genes (vP 1043), a vaccinia virus expressingthe gI(gB), gIII(gC) and gIV(gD) genes of BHV-1, a canarypox expressinggD of FHV-1, or alternatively recombinants expressing the gII(gB),gIII(gC) and gp50(gD) of PRV. They can also refer to WO-A-95/26 751(incorporated by reference), which describes recombinant viruses vCP320,vCP322 and vCP294 expressing the gB, gC and gD genes, respectively, ofCHV. They can also refer to the recombinants expressing FHV, PRV and BHVgenes in FR-A-2 647 808, or WO-A-9012882, incorporated by reference.

The invention also proves particularly advantageous for vaccinationagainst influenza viruses, as demonstrated here for EIV (equineinfluenza virus). There may also be mentioned avian influenza (AIV) and,porcine influenza (swine influenza virus).

By way of example, persons skilled in the art can refer to therecombinant canarypox expressing the HA gene of EIV in WO-A-92 15 672.

The subject of the invention is therefore recombinant live vaccinescomprising at least one viral vector incorporating and expressing atleast one gene of such an influenza virus, and at least one adjuvant inaccordance with the invention. In particular, the vaccine comprises amixture of two or three vectors each incorporating and expressing an HAgene, the genes being obtained from different strains, for exampleequine influenza strains Prague, Kentucky and Newmarket. Similarly, asingle vector may be used to incorporate and express the HAs of 2 or ofthe 3 strains.

The invention also applies to other animal pathogens, such as inparticular FeLV (see also canarypox recombinants in WO-A-92 15672 by wayof example, expressing env, gag=vCP93 and vCP97), tetanus (see alsoWO-A-92 15672 and the recombinants vCP161 and vP1075, canarypox andvaccinia, expressing the tetanus toxin), Carré's disease virus (caninedistemper virus or CDV) (see recombinant vCP 258 in WO-A-95 27780,incorporated by reference).

The subject of the invention is therefore recombinant live vaccinescomprising at least one viral vector incorporating and expressing atleast one gene of such a virus.

The subject of the invention is also multivalent recombinant vaccines,that is to say containing two or more recombinant vectors expressingantigens of two or more diseases, in the form of a mixture in anadjuvant solution in accordance with the invention.

Moreover, the invention applies to the use of any type of viralexpression vector, such as poxvirus (vaccinia virus, including NYVACaccording to WO-A-92/15672, fowlpox, canarypox, pigeonpox, swinepox andthe like), adenovirus, herpesvirus. Canarypox, e.g. ALVAC (WO-A-95/27780and WO-A-92/15672) is found to be particularly appropriate in thecontext of the present invention.

In a ready-for-use, especially reconstituted, vaccine, the viral vectoris present in the quantities normally used and described in theliterature.

The recombinant live vaccines generally exist in a freeze-dried formallowing their storage and are reconstituted immediately before use in asolvent or excipient, which will be here the solution of adjuvant inaccordance with the invention.

The subject of the invention is therefore also a vaccination setcomprising, packaged separately, freeze-dried vaccine and a solution ofthe adjuvant compound according to the invention for the reconstitutionof the freeze-dried vaccine.

The subject of the invention is also a method of vaccination consistingin administering, by the parenteral, preferably subcutaneous,intramuscular or intradermal, route or by the mucosal route a vaccine inaccordance with the invention at the rate of one or moreadministrations, optionally with a preliminary step of reconstitutingthe freeze-dried vaccine (the recombinant vector) in a solution ofadjuvant compound.

One objective of such a method may be to protect animals from theclinical point of view and to reduce viral excretion, which correspondsin particular to the case of herpesviruses.

Another objective may be to increase the immune response and to make itoccur earlier, especially by inducing antibodies starting from the firstadministration.

The subject of the invention is also the use of the adjuvant compoundsin accordance with the invention for the production of recombinant livevaccines, especially conferring an improved and earlier immune responseand/or an increased reduction in viral excretion. Reference may be madeto what was said above.

EXAMPLES Example 1 Generation of the Donor Plasmids for the Sites ofInsertion C3, C5 and C6 Into the Canarypox Virus “ALVAC”

The donor plasmids for the different sites of insertion into thecanarypox virus “ALVAC” (Tartaglia et al. Virology, 1992. 188. 217-232,incorporated by reference) are described in Application WO-A-95/27780,Example 20.

These plasmids were designated in this application in the followingmanner:

“plasmid VQH6CP3LSA.2” for the “C3” site

“plasmid HC5LSP28” for the “C5” site

“plasmid pC6L” for the “C6” site.

EXAMPLE 2 Generation of the Recombinant Virus vCP258 (ALVAC/CDV HA+F)

The Onderstepoort strain of the CDV virus was used to isolate the HA andF genes (sequence of the HA gene described by Curran et al. Virology.1991. 72. 443-447, and sequence of the F gene described by Barrett etal. Virus Research. 1987. 8. 373-386, both incorporated by reference).

The construction of the donor plasmid pMM103 for the insertion of theexpression cassettes H6 vaccinia promoter-CDV F gene and H6 vacciniapromoter-CDV HA gene into the C6 locus of the ALVAC virus is describedin Example 19 of Application WO-A-95/27780.

This plasmid was used as donor plasmid for in vitro recombination(Piccini et al. Methods in Enzymology. 1987. 153. 545-563, incorporatedby reference), with the ALVAC virus to generate the recombinant virusdesignated vCP258 as in Example 19 of the abovementioned application.

EXAMPLE 3 Generation of the Recombinant Virus vCP1502 (ALVAC/EIV HAPrague)

The sequence of the HA gene (EIV Prague strain) is presented in FigureNo. 23 of Application WO-A-92/15672. The viral RNA of the genome of theequine influenza virus strain Prague 56 was extracted from 100 μl of aviral suspension of this virus with the “Total RNA Separator kit”extraction kit from CLONTECH (Palo Alto, Calif.) (Cat #K1042-1). The RNApellet was taken up in 10 μl of ultrapure water and a complementary DNAsynthesis reaction, followed by a PCR reaction (=“RT-PCR” reaction) wascarried out taking as template 2 μl of purified viral RNA and thefollowing oligonucleotides:

TAY51A (SEQ ID NO:3) (70 mer)

5′CGCGGCCATCGCGATATCCGTTAAGTTTGTATCGTAATGAACACTCAAATTCTAATATTAGCCACTTCGG3′

and TAY53A (SEQ ID NO:4) (36 mer)

5′CGCGCGGCGGTACCTTATATACAAATAGTGCACCGC3′

in order to amplify the Prague EIV HA gene. The PCR fragment thusobtained was ligated into the vector pCRII (Invitrogen, San Diego,Calif.) to give the plasmid pJT007.

The plasmid pJT007 was digested with NruI and Asp718 in order to isolatean NruI-718 fragment of about 1800 bp containing the end of the H6promoter and the Prague 56 HA gene in its entirety. This fragment wasligated with the donor plasmid C5 HC5LSP28, previously digested withNruI and Asp718, to finally give the plasmid pJT008. This plasmidcontains the expression cassette H6-Prague 56 HA gene in the C5 locus ofthe ALVAC virus. The structure of this plasmid was verified bysequencing and complete restriction map.

This plasmid is the donor plasmid for the insertion of the expressioncassette H6-Prague 56 HA gene into the 5 locus.

After linearizing with NotI, the plasmid pJT008 was used as donorplasmid for in vitro recombination (Piccini et al. Methods inEnzymology. 1987. 153. 545-563) with the ALVAC virus in order togenerate the recombinant virus designated vCP1502.

EXAMPLE 4 Generation of the Recombinant Virus vCP1529 (ALVAC/EIV HAKentucky 1/94)

The viral RNA of the genome of the equine influenza virus strainKentucky 1/94 (Daly et al. J. Gen. Virol. 1996. 77. 661-671,incorporated by reference) was extracted with 100 μl of a viralsuspension of this virus with the “Total RNA Separator kit” extractionkit from CLONTECH (Palo Alto, Calif.) (Cat #K1042-1). The RNA pellet wastaken up in 10 μl of ultrapure water and RT-PCR reaction was carried outtaking as template 2 μl of purified viral RNA and the followingoligonucleotides:

TAY55A (SEQ ID NO:5) (70 mer)

5′CGCGGCCATCGCGATATCCGTTAAGTTTGTATCGTAATGAAGACAACCATTATTTTGATACTACTGACCC3′

and TAY57A (SEQ ID NO:6) (42 mer)

5′CGCGCGGCGGTACCTCAAATGCAAATGTTGCATCTGATGTTG3′

in order to amplify the HA gene. The PCR fragment thus obtained wasligated into the vector pCRII (Invitrogen, San Diego, Calif.) to givethe plasmid pJT001. The sequence of the Kentucky 1/94 strain EIV HA genecloned into the plasmid pJT001 is not different from the sequence of theKentucky 1/94 strain EIV HA gene available in the GenBank databank(accession number L39914, incorporated by reference)

The plasmid pJT001 containing the HA gene (Kentucky 1/94) was digestedwith NruI and Asp718 in order to isolate an NruI-Asp718 fragment of 1800bp (containing the end of the H6 promoter and the Kentucky 1/94 HA genein its entirety). This fragment was ligated with the donor plasmid C5HC5LSP28, previously digested with NruI and Asp718, to finally give theplasmid pJT005. This plasmid contains the expression cassetteH6-Kentucky 1/94 HA gene in the C5 locus of the ALVAC virus. Thestructure of this plasmid was verified by sequencing and completerestriction mapping.

This plasmid is a donor plasmid for the insertion of the expressioncassette H6-Kentucky 1/94 HA gene into the C5 locus.

After linearizing with NotI, the plasmid pJT005 was used as donorplasmid for in vitro recombination (Piccini et al. Methods inEnzymology. 1987. 153. 545-563) with the ALVAC virus in order togenerate the recombinant virus designated vCP1529.

EXAMPLE 5 Generation of the Recombinant Virus vCP1533 (ALVAC/EIV HANewmarket 2/93)

The viral RNA of the genome of the equine influenza virus strainNewmarket 2/93 (Daly et al. J. Gen. Virol. 1996. 77. 661-671) wasextracted from 100 μl of a viral suspension of this virus with the“Total RNA Separator kit” extraction kit from CLONTECH (Cat #K1042-1).The RNA pellet was taken up in 10 μl of ultrapure water and an RT-PCRreaction was carried out taking as template 2 μl of purified viral RNAand the following oligonucleotides:

CCL007 (SEQ ID NO:7) (40 mer)

5′TTGTCGACTCAATCATGAAGACAACCATTATTTTGATACT3′

and CCL0018 (SEQ ID NO:8) (34 mer)

5′TTGGATCCTTACTCAAATGCAAATGTTGCAYCTG3′

in order to amplify the HA gene. The PCR fragment thus obtained wasligated to the vector pCRII (InVitrogen, San Diego, Calif.) to give theplasmid pCCL026. The sequence of the HA gene (EIV Newmarket 2/93 strain)is presented in Figure No. 1 (SEQ ID NO:1).

The plasmid pCCL026 containing the HA gene (Newmarket 2/93 strain) wasdigested with SpeI and AccI. The following oligonucleotides:

TAY99N (SEQ ID NO:9) (74 mer)

5′CTAGTTCGCGATATCCGTTAAGTTTGTATCGTAATGAAGACAACCATTATTTTGATACTACTGACCCATTGGGT3′

and TAY100N (SEQ ID NO:10) (72 mer)

5′AGACCCAATGGGTCAGTAGTATCAAAATAATGGTTGTCTTCATTACGATACAAACTTAACGGATATCGCGAA3′

were annealed and ligated with the plasmid pCCL026 digested withSpeI+AccI to give the plasmid pJT003. The double-strandedoligonucleotide TAY99N/TAY100N contains the 3′ region of the H6 promoterup to the NruI site and the first 40 coding bases of the HA gene.

The plasmid JT003 was digested with NruI and XhoI in order to isolate anNruI-XhoI fragment of about 1800 bp containing the end of the H6promoter and the HA gene in its entirety. This fragment was ligated withthe donor plasmid C5 HC5LSP28, previously digested with NruI and XhoI,to finally give the plasmid pJT004. This plasmid contains the expressioncassette H6-Newmarket 2/93 HA gene in the C5 locus of the ALVAC virus.The structure of this plasmid was verified by sequencing and completerestriction mapping.

This plasmid is the donor plasmid for the insertion of the expressioncassette H6-Newmarket 2/93 HA gene into the C5 locus.

After linearizing with PvuI, the plasmid pJT004 was used as donorplasmid for the in vitro recombination (Puccini et al. Methods inEnzymology. 1987. 153. 545-563) with the ALVAC virus in order togenerate the recombinant virus designated vCP1533.

EXAMPLE 6 Generation of the Recombinant Virus VCP132 (ALVAC/EHV-1gB+gC+gD)

The construction of the recombinant virus is described in Examples 25and 26 of Application WO-A-92/15672. This virus was generated by invitro recombination between the ALVAC virus and the donor plasmidpJCA049. This plasmid contains the following 3 expression cassettescloned into the site of insertion C3:

I3L vaccinia promoter-EHV-1 gB gene

H6 vaccinia promoter-EHV-1 gC gene

42K entomopox promoter-EHV-1 gD gene

The sequences of the EHV-1 gB, gC and gD genes are described inApplication WO-A-92/15672 in Figures No. 2 (sequence of the EHV-1 genegp13=gC), No. 6 (sequence of the EHV-1 gene gp14=gB) and No. 12(sequence of the EHV-1 genes gD, gp63 and gE).

EXAMPLE 7 Generation of the Recombinant Virus vCP243 (ALVAC/FHV-1gB+gC+gD)

The sequence of the FHV-1 gB gene (CO strain) is presented in Figure No.34 of Application WO-A-90/12882.

The FHV-1 gC gene (CO strain) (sequence presented in Figure No. 2) (SEQID NO: 2) was cloned from the EcoRI F fragment (7.6 kbp). It has a sizeof 1599 bp and encodes a protein of 533 amino acids.

The FHV-1 gD gene (CO strain) (sequence presented in Figure No. 28 ofApplication WO-A-92/15672) was cloned from the EcoRI M fragment (4.4kbp) (plasmid pFHVEcoRIM).

Construction of the Expression Cassette I3L-FHV-1 gB Gene Mutated at theLevel of the Signals for Early Termination of Transcription (TTTTTNT)

The following oligonucleotides:

MP287 (SEQ ID NO: 11) (20 mer)

5′GATTAAACCTAAATAATTGT3′

and JCA158 (SEQ ID NO:12) (21 mer)

5′TTTTTCTAGACTGCAGCCCGGGACATCATGCAGTGGTTAAAC3′

were used for a PCR amplification with the template of a plasmidcontaining the I3L vaccinia promoter (Rivière et al. J. Virol. 1992. 66.3424-3434, incorporated by reference) in order to generate a blunt-endedXbaI fragment of 120 bp (containing the I3L vaccinia promoter)=fragmentA. The following oligonucleotides:

JCA213 (SEQ ID NO: 13) (18 mer)

5′GGGTTTCAGAGGCAGTTC3′

and JCA238 (SEQ ID NO: 14) (21 mer)

5′ATGTCCACTCGTGGCGATCTT3′

were used to generate, by PCR from the template of the plasmid pJCA001,a blunt-ended BamHI fragment of 720 bp (containing the 5′ part of theFHV-1 gB gene)=fragment B.

Fragment A was digested with XbaI, and then phosphorylated. Fragment Bwas digested with BamHI, and then phosphorylated. Fragments A and B werethen ligated together with the vector pBluescript SK+, previouslydigested with XbaI and BamHI, to give the plasmid pJCA075.

The following oligonucleotides:

JCA158 (SEQ ID NO: 15) and JCA211 (SEQ ID NO: 16) (21 mer):

5′GTGGACACATATAGAAAGTCG3′

were used to generate, by PCR from the template of the plasmid pJCA075,a blunt-ended XbaI fragment of 510 bp (containing the I3L promoter fusedto the 5′ part of the FHV-1 gB gene mutated at the level of the signalTTTTTNT)=fragment C.

The following oligonucleotides:

JCA212 (SEQ ID NO: 17) 21 mer)

5′CACCTTCAGGATCTACTGTCG3′

and JCA213 (SEQ ID NO: 13) (18 mer)

were used to generate, by PCR from the template of the plasmid pJCA001,a blunt-ended BamHI fragment of 330 bp (containing the central part ofthe FHV-1 gB gene)=fragment D.

Fragment C was digested with XbaI, and then phosphorylated. Fragment Dwas digested with BamHI, and then phosphorylated. Fragments C and D werethen ligated together with the vector pBluescript SK+, previouslydigested with XbaI and BamHI to give the plasmid pJCA076.

The following oligonucleotides:

JCA239 (SEQ ID NO: 18) (24 mer)

5′ACGCATGATGACAAGATTATTATC3′

and JCA249 (SEQ ID NO: 19) (18 mer)

5′CTGTGGAATTCGCAATGC3′

were used to generate, by PCR from the template of the plasmid pJCA001,a blunt-ended EcoRI fragment of 695 bp (containing the first 3′ part ofthe FHV-1 gB gene)=fragment E. The following oligonucleotides:

JCA221 (SEQ ID NO: 20) (48 mer)

5′AAAACTGCAGCCCGGGAAGCTTACAAAAATTAGATTTGTTTCAGTATC3′

and JCA247 (SEQ ID NO: 21) (36 mer)

5′GGTATGGCAAATTTCTTTCAGGGACTCGGGGATGTG3′

were used to generate, by PCR from the template of the plasmid pJCA001,a blunt-ended PstI fragment of 560 bp (containing the second 31 part ofthe FHV-1 gB gene mutated at the level of the signal TTTTTNT)=fragmentF.

Fragment E was digested with EcoRI, and then phosphorylated. Fragment Fwas digested with PstI, and then phosphorylated. Fragments E and F werethen ligated together with the vector pIBI24 (InternationalBiotechnologies Inc., New Haven, Conn.), previously digested with EcoRIand PstI, to give the plasmid pJCA077 (containing the cassette I3Lvaccinia promoter FHV-1 B gene).

Construction of the Expression Cassette 42K-FHV-1 gD

The following oligonucleotides:

RG286 (SEQ ID NO: 22) (17 mer)

5′TTTATATTGTAATTATA3′

and M13F (SEQ ID NO: 23) (17 mer)

5′GTAAAACGACGGCCAGT3′

were used to generate, by PCR from the template of the plasmidcontaining the 42K Entomopoxvirus AmEPV promoter (described in Example21 of Patent U.S. Pat. No. 5,505,941), a blunt-ended EcoRI fragment of130 bp (containing the 42K entomopox promoter)=fragment A. The followingoligonucleotides:

JCA234 (SEQ ID NO: 24) (21 mer)

5′ATGATGACACGTCTACATTTT3′

and JCA235 (SEQ ID NO: 25) (21 mer)

5′TGTTACATAACGTACTTCAGC3′

were used to generate by PCR from the template of the plasmidpFHVEcoRIM, a blunt-ended BamHI fragment of 185 bp (containing the 5′part of the FHV-1 gD gene)=fragment B. Fragment A was digested withEcoRI, and then phosphorylated. Fragment B was digested with BamHI, andthen phosphorylated. Fragments A and B were then ligated together withthe vector pBluescript SK+, previously digested with EcoRI and BamHI, togive the plasmid pJCA078.

The plasmid pFHVEcoRIM (see above) was digested with BamHI and XhoI inorder to isolate the BamHI-XhoI fragment of 1270 bp (containing the 3′part of the FHV-1 gD gene). This fragment was then ligated with thevector pIBI24, previously digested with BamHI and XhoI, in order to givethe plasmid pJCA072. The following oligonucleotides:

JCA242 (SEQ ID NO:26) (18 mer)

5′GAGGATTCGAAACGGTCC3′

and JCA237 (SEQ ID NO:27) (53 mer)

5′AATTTTCTCGAGAAGCTTGTTAACAAAAATCATTAAGGATGGTAGATTGCATG3′

were used to generate, by PCR from the pFHVEcoRIM template, an XbaI-XhoIfragment of 290 bp. This fragment was digested with XbaI andXhoI=fragment C (containing the end of the FHV-1 gD gene).

The plasmid pJCA072 was digested with XbaI and XhoI in order to isolatethe XbaI-XhoI fragment of 3575 bp (vector pIBI24+start of the 3′ part ofthe FHV-1 gD gene)=fragment D. Fragments C and D were then ligatedtogether in order to give the plasmid pJCA073.

The plasmid pJCA073 was digested with BamHI and XhoI in order to isolatethe BamHI-XhoI fragment of 960 bp (containing the 3′ part of the FHV-1gD gene)=fragment A. The plasmid pJCA078 was digested with HpaI andBamHI in order to isolate the HpaI-BamHI fragment of 310 bp (containingthe 42K promoter fused to the 5′ part of the FHV-1 gD gene)=fragment B.Fragments A 5 and B were ligated together with the vector pBluescriptSK+, previously digested with EcoRV and XhoI, in order to give theplasmid pJCA080 (containing the cassette 42K promoter-FHV-1 gD gene).

Construction of the Cassette H6-FHV-1 gC

The genomic DNA of the FHV-1 virus (CO strain) was digested with EcoRIand the EcoRI F fragment of about 7500 bp was cloned into pBluescriptSK+ to give the plasmid pFHVEcoRIF. The following oligonucleotides:

JCA274 (SEQ ID NO: 28) (55 mer)

5′CATTATCGCGATATCCGTTAAGTTTGTATCGTAATGAGACGATATAGGATGGGAC3′

and JCA275 (SEQ ID NO: 29) (18 mer)

5′ACTATTTTCAATACTGAC3′

were used to generate, by PCR from the pFHVEcoRIF template, a fragmentwhich was digested with NruI and SalI in order to give an NruI-SalIfragment of 107 bp (containing the 3′ part of the H6 vaccinia promoterfused to the 5′ part of the FHV-1 gC gene)=fragment A.

The following oligonucleotides:

JCA276 (SEQ ID NO: 30) (18 mer)

5′AAATGTGTACCACGGGAC3′

and JCA277 (SEQ ID NO: 31) (54 mer)

5′AAGAAGCTTCTGCAGAATTCGTTAACAAAAATCATTATAATCGCCGGGGATGAG3′

were used to generate, by PCR from the pFHVEcoRIF template, a fragmentwhich was digested with EcoRV and HindIII in order to give anEcoRV-HindIII fragment of 370 bp (containing the 3′ part of the FHV-1 gCgene and the HpaI-EcoRI-PstI-HindIII sites)=fragment B.

The plasmid pJCA020 (see above) was digested with NruI and HindIII inorder to isolate the HindIII-NruI fragment (containing the 5′ part ofthe H6 vaccinia promoter)=fragment C. The plasmid pFHVEcoRIF wasdigested with BamHI and EcoRV in order to isolate the BamHI-EcoRVfragment of 580 bp (containing the central part of the FHV-1 gCgene)=fragment D. Fragments A and C were ligated together with thevector pBluescript SK+, previously digested with HindIII and SalI inorder to give the plasmid pJCA097. Fragments B and D were ligatedtogether with the vector pBluescript SK+, previously digested with BamHIand HindIII, to give the plasmid pJCA099.

The plasmid pJC097 was digested with PstI and SalI in order to isolatethe PstI-SalI fragment of 200 bp (containing the cassette H6-5′ part ofgC)=fragment E. The plasmid pFHV1EcoRIF was digested with BamHI and SalIin order to isolate the SalI-BamHI fragment of 600 bp (2nd central partof FHV-1 gC)=fragment F. Fragments E and F were then ligated togetherwith the vector pBluescript SK+, previously digested with BamHI andPstI, in order to give the plasmid pJCA098. The plasmid pJCA098 was thendigested with EcoRI and BamHI in order to isolate the EcoRI-BamHIfragment of 820 bp (containing the cassette H6-5′ part ofFHV-1gC)=fragment G. The plasmid pJCA099 (see above) was digested withBamHI and HindIII in order to isolate the BamHI-HindIII fragment of 960bp (containing the 3′ part of the FHV-1 gC gene)=fragment H. Fragments Gand H were then ligated together with the vector pBluescript SK+,previously digested with EcoRV and HindIII, in order to give the plasmidpJCA100 (containing the expression cassette H6 vaccinia promoter-FHV-1gC gene).

The plasmid pJCA100 was digested with NruI and EcoRI in order to isolatethe NruI-EcoRI fragment of 1650 bp containing the 3′ part of the H6promoter fused with the FHV-1 gC gene. This fragment, was ligated withthe plasmid pJCA053 (cassette VQH6-IBV M in the vector pBluescript SK+),previously digested with NruI and EcoRI, in order to give the plasmidpJCA108 (containing the cassette VQH6-gC in pBluescript SK+). Theplasmid pJCA079 (see above) was digested with SmaI and BamHI in order toisolate the BamHI-SmaI fragment of 840 bp (containing the cassetteI3L-5′ part of the FHV-1 gB gene)=fragment A. The plasmid pJCA079 wasalso digested with BamHI and HindIII in order to isolate theBamHI-HindIII fragment of 2155 bp (containing the 3′ part of the FHV-1gB gene)=fragment B. The plasmid pJCA108 (see above) was digested withHindIII and EcoRI in order to isolate the HindIII-EcoRI fragment of 1830bp (containing the cassette VQH6-FHV-1 gC)=fragment C. The plasmidpJCA080 (see above) was digested with EcoRI and XhoI in order to isolatethe EcoRI-XhoI fragment of 1275 bp (containing the cassette 42K-FHV-1 gDgene)=fragment D. Fragments A, B, C and D were then ligated togetherwith the donor plasmid pC6L in order to give the plasmid pJCA109.

This plasmid contains the expression cassettes H6-FHV-1 gene gC,I3L-FHV-1 gB gene and 42K-FHV-1 gD gene in the C6 locus of the ALVACvirus. The structure of this plasmid was verified by sequencing andcomplete restriction map.

This plasmid is the donor plasmid for the insertion of the expressioncassettes H6-FHV-1 gC gene, I3L-FHV-1 gB gene and 42K-FHV-1 gD gene inthe C6 locus of the ALVAC virus.

After linearizing with NotI, the plasmid pJCA109 was used as donorplasmid for in vitro recombination (Piccini et al. Methods inEnzymology. 1987. 153. 545-563) with the ALVAC virus in order togenerate the recombinant virus designated vCP243.

EXAMPLE 8 Adjuvant

The carbomer used in the vaccines in accordance with the presentinvention is Carbopol® 974P manufactured by the company BF Goodrich (MWabout 3 million).

A stock solution containing 1.5% w/v of Carbopol® 974P was firstprepared in distilled water containing sodium chloride at 1 g/l.

This stock solution is then used for the manufacture of a solution ofCarbopol® in physiological saline at 4 mg/ml. The stock solution ispoured into the entire physiological saline (or optionally into most ofit) all at once or optionally in several portions with, each time,adjustment of the pH with the aid of NaOH (for example 1 N or moreconcentrated) to a value of about 7.3 to 7.4.

A ready-for-use solution of Carbopol® is thereby obtained which can beused by the final user to reconstitute a freeze-dried recombinantvaccine.

EXAMPLE 9 Vaccination of Horses With the Aid of the RecombinantCanarypox Vector vCP132 (See Example 6) Expressing the Glycoproteins gB,gC and gD of the Type I Equine Herpesvirus (EHV-1)

1. Protocol for Immunization and Challenge:

20 ponies (Welsh mountain ponies) exhibiting no serological signsindicating a recent exposure to EHV-1 and EHV-4 were randomlydistributed into 4 groups (A to D) of 5 ponies.

Groups A and B were vaccinated with the recombinant canarypox vCP132expressing the glycoproteins gB, gC and gD of the Kentucky D strain ofEHV-1. The vaccine was reconstituted in sterile water (group A) or in asolution of carbomer 4 mg/ml (group B) according to Example 8.

Group C was vaccinated with a commercial inactivated whole EHV vaccinecontaining, in a dose volume of 1.5 ml, inactivated EHV-1 and EHV-4valencies and 6 mg of carbomer.

Group D is the control group in which the animals were vaccinated with arecombinant canarypox virus vCP1502 expressing the HA glycoprotein ofthe Influenza A/equi-1/Prague56 virus (see Example 3) reconstituted incarbomer under the same conditions as for group B.

The vaccines are described in detail in Table 1:

Diluent/ Dose Groups Vaccines Antigens adjuvant (1 ml) A vCP132 EHV-1Sterile 10^(8.0)TCID₅₀ water B vCP132 EHV-1 Carbopol ® 10^(8.0)TCID₅₀974P C Commercial EHV-1 Carbopol ® 10^(7.3)TCID₅₀ vaccine EHV-4 beforeinactivation EHV-1 10^(7.3)TCID₅₀ before inactivation EHV-4 D vCP1502HA-Prague Carbopol ® 10⁸TCID₅₀ 56 974P

Each animal received 1 dose of vaccine corresponding to D0 and D35 bydeep intramuscular injection into the neck.

On D56, the ponies were challenged by intranasal instillation of10⁵TCID₅₀ of the Ab4/8 strain of EHV-1.

2. Serological Tests

Neutralization tests SN were carried out according to the techniquedescribed in Thompson et al., Equine Vet. J., 8, 58-65, 1976. The EHV-1virus (RACH) was used as antigen.

The SN titres are expressed as the reciprocal of the serum dilutiongiving 50% neutralization (log₁₀).

3. Virological Monitoring:

The expression of the virus was monitored daily over 10 days usingnasopharyngeal swabs which were collected in virus transporting medium.The swab extracts were titrated on rabbit kidney cells RK13 inmicrotitre plates. The titres were calculated using the Karber formulaexpressed in log₁₀ TCID₅₀ per 1 ml.

4. Results:

No significant local or systemic reaction was noted following thesevaccinations.

The seroneutralization SN antibody mean responses (log 10 of thedilution causing 50% neutralization) are:

Titre on D.56 Group Titre on D.0 (before challenge) A 1.69 ± 0.49 1.93 ±0.15 B 1.69 ± 0.47 2.61 ± 0.42 C 1.19 ± 0.30 2.47 ± 0.32 D 1.57 ± 0.451.55 ± 0.37

A significant increase in the antibody titre is observed with thevaccine vCP132 in carbomer.

All the 5 control ponies excrete the virus through the nasopharynx. Theviral excretion in these nonvaccinated ponies continued for an averageof 5 days, with a maximum viral excretion at 4 days post-infection.

All the ponies in groups A, C and D excrete a virus after challenge. Bycontrast only two ponies out of the 5 ponies in group B vaccinatedaccording to the invention excrete the virus. In addition, the quantityof virus excreted in group B is significantly less than the quantityexcreted by the other groups including group C. Likewise, the durationof excretion in the animals in group B is much shorter than in the othergroups.

Reference may be made to FIG. 1 and to the area under the curve valuesgiven below, which show very clearly the virtual absence of viralexcretion in the ponies vaccinated with vCP132 in the presence ofcarbomer. The result is very significant if it is compared in particularwith the commercial vaccine. A significant reduction in viral excretionis observed in the animals in group B compared with the controls,whereas no significant difference is observed between the animals ingroup C and the controls. This reduction by a remarkable and unexpectedlevel in the excretion of virus is particularly advantageous because ofits very favourable indications on the limitation of the transmission ofthe virus from horse to horse. Total virus per pony (area under thecurve):

A: 17.1 B: 3.0 C: 9.7 D: 16.3

EXAMPLE 10 Vaccination of Horses With the Aid of the Canarypox VectorvCP1533 (See Example 5) Recombinant Expressing the HA Glycoprotein ofthe Influenza A/equi-2/Newmarket/2/93 Virus in the Presence of Carbomer

1. Protocol for Immunization and Challenge:

20 ponies (Welsh mountain ponies), 7 to 8 months old having nodetectable antibodies against the H3N8 and H7N7 viruses, measured by theSRH (for single radial haemolysis) test were used in this study. Thenegative status of the animals makes it possible to study, under thebest conditions, the efficacy of the various vaccines in terms ofhumoral response. The ponies were randomly distributed into 4 groups (Ato D) of 5 to 6 ponies.

The ponies in group A were vaccinated with the aid of a recombinantcanarypox (vCP1533) expressing the HA glycoprotein of the influenzaA/equi-2/Newmarket/2/93 virus. This vaccine was reconstituted in asolution containing 4 mg/ml of carbomer, Carbopol® 974P.

Group B was vaccinated with a commercial vaccine containing, in a dosevolume of 1.5 ml, a mixture of 3 inactivated strains of influenza,namely Prague/56, Suffolk/89 and Miami/63, tetanus toxoid, as well ascarbomer (4 mg) and aluminium hydroxide (2.2 mg) as adjuvants.

Group C was vaccinated with the aid of a vaccine C comprising 2influenza inactivated valencies, namely Prague/56, Newmarket/2/93 aswell as tetanus toxoid in aluminium hydroxide.

Group D was vaccinated with the aid of a recombinant canarypox vectorvCP132 seen above and reconstituted with a solution containing 4 mg/mlof carbomer 974P. The latter group served as control for the challenge.

The vaccines are described in detail in Table II:

Diluent/ Dose Groups Vaccines Antigens adjuvant (1 ml) A vCP1533 HA-Carbopol ® 10^(7.7)TCID₅₀ Newmarket/2/93 974P B Commercial Prague/56;Carbopol ® 15 μg HA of vaccine Suffolk/89 Al(OH)₃ each strain Miami/63;tetanus toxoid C Vaccine C Prague/56; Al(OH)₃ 15 μg HA of Newmarket/2/93each strain tetanus toxoid D vCP132 gB, gC, gD- Carbopol ®10^(8.0)TCID₅₀ EHV-1 974P

2 doses of 1 ml of each vaccine were administered to each animal at aninterval of 5 weeks by deep intramuscular injection into the neck.

2 weeks after the second vaccination, each pony was infected by exposureto an aerosol obtained from about 20 ml of allantoic fluid for a totalof 10^(7.3) EID₅₀ of influenza A-equi-2-/Sussex/89 virus, using an ULTRA2000 model spraying device (De Villbiss, Somerset Pa.) as described byMumford et al, Equine Vet, J., 22: 93-98, 1990.

2. Serological Test:

Samples of whole blood were collected on the following days: 0 (the sameday as and before the first vaccination), 7, 14, 35 (the same day as andbefore the second vaccination), 49 (the same day as and before thechallenge), 56 and 63.

The serum was prepared and stored and preserved by freezing at −20° C.until it is used. All the sera were tested for the presence of SRHantibody against Influenza A/equi-1/Prague/56 and InfluenzaA/equi-2/Newmarket/2/93 as described by Wood et al. (J. Hyg., 90:371-384, 1983).

The diameters of the haemolysis zones were measured in two directions atright angles using an automated reader. The surface area of the zoneswas calculated and an increase of 50% was considered as beingsignificant. The titres were expressed in mm² of haemolysis.

3. Virological Monitoring.

Viral excretion was monitored daily over 10 days by collecting nasopharyngeal swabs in a virus transporting medium. The exudate from eachswab was diluted by 10-fold serial dilutions in PBS at pH 7.2 and 0.1 mlof each dilution was inoculated into the allantoic space of 10 day-oldembryonated eggs. The viral titre (EID₅₀/ml) in the swab extracts wascalculated from the haemagglutinating activity in the allantoic fluidscollected after incubating the eggs at 34° C. for 72 hours.

4. Results.

No significant local or systemic reaction was observed following thefirst vaccination with the exception of one horse in group B.

It should be noted that the strains Suffolk and Newmarket are similar(Daly et al., J. Gen. Virol. 1996, 661-671) which makes comparison withthe commercial vaccine perfectly valid under the trial conditions.

None of the ponies had a detectable SRH antibody against InfluenzaA/equi-2/Newmarket/2/93 or Influenza A/equi-1/Prague/56 at the beginningof the study. The serological results 1 week after the first vaccinationshowed that none of the ponies was previously infected with Influenza(no observable booster effect).

2 weeks after the first vaccination, none of the ponies developed adetectable antibody response against Influenza A/equi-1/Prague/56. Inaddition, there was no detectable SRH antibody against InfluenzaA/equi-2/Newmarket/93 in 6 animals out of 6 vaccinated with vaccine C,in 4 animals out of 5 vaccinated with the commercial vaccine B and inthe control group D. By contrast, a very high SRH antibody titre wasobserved in all the 5 ponies vaccinated with canarypox in the presenceof the carbomer adjuvant: mean 155.4±32.9. Table III below presents theresults obtained animal per animal as regards the SRH antibody titres.

TABLE III SRH results (mm²) PRAGUE NEWMARKET Ponies Group (D0, D7, D14)D0 D7 D14 M26 A 0 0 0 158.0 M27 A 0 0 0 104.2 M28 A 0 0 0 160.3 M29 A 00 0 196.4 M30 A 0 0 0 158.0 M31 B 0 0 0 0 M32 B 0 0 0 0 M33 B 0 0 0 0M34 B 0 0 0 0 M35 B 0 0 0 81.2 M36 C 0 0 0 0 M37 C 0 0 0 trace M38 C 0 00 0 M39 C 0 0 0 0 M40 C 0 0 0 trace M41 C 0 0 0 0 M42 D 0 0 0 0 M43 D 00 0 0 M44 D 0 0 0 0 M45 D 0 0 0 0 M46 D 0 0 0 0

The vaccine according to the invention leads to the appearance of a highantibody titre from 14 days after the first vaccination whereas,overall, for vaccines B and C, the first vaccination does not cause onthis date the appearance of antibodies at detectable levels. Such anearly production of such a titre is a remarkable and unexpected resultwhich has never been observed before.

EXAMPLE 11 Vaccination of Horses With the Aid of the Canarypox VectorvCP1502 (See Example 3) Recombinant Expressing the HA Glycoprotein ofthe Influenza A/equi-1/Prague 56 Virus in the Presence of Carbomer

The controls of Example 1, vaccinated with vCP1502, were also monitoredfrom the serological point of view.

Table IV below shows the IHA (inhibition of haemagglutination) titresobtained in the animals immunized with 10⁸ pfu of vCP1502 with Carbopol®974P at 0 (1st injection V1) and 35 (2nd injection V2) days.

TABLE IV Anti-H7N7 IHA titres Day 0 Day 35 Ponies (V1) Day 7 Day 14 (V2)Day 56 RM16 0 0 128 64 128 RM17 0 0 32 128 256 RM18 0 0 16 64 512 RN19 00 32 32 256 RM20 0 0 128 64 128

As in the preceding example, it is observed that the injection of acanarypox-EIV (expressing the HA gene of the A equi-1/Prague virus)mixed with carbomer allows high specific IHA titres to be obtained fromD14 after a vaccination. Remarkably, these high titres are furthersignificantly increased after a booster, reaching a very high meantitre, of a level which has never been observed before for the HAantigen of EIV H7N7 virus on horses which have not undergonepromostimulation.

EXAMPLE 12 Application in Cats

The recombinant virus tested is a recombinant canarypox virus expressingthe gB, gC and gD genes of the feline herpesvirus (FelineHerpesvirus=FHV). This recombinant virus is identified vCP243 (seeExample 7).

The protocol for vaccination/challenge in the FHV model is thefollowing.

Number of Diluent/ Group cats Vaccine adjuvant Dose A 6 vCP243 water10^(7.5) pfu B 6 vCP243 Carbopol ® 10^(7.5) pfu 974P C 6 CORIFELIN ® — 1commercial dose D 6 — — — (controls)

The cats are vaccinated on D0 and D28 by the subcutaneous route.

The vaccine CORIFELIN® is a subunit FHV vaccine marketed by Mérial,Lyon, France, comprising at least 200 IDR units of FHV viral fractions,25 μg of purified feline calicivirus antigen, 0.1 mg of thiomersal andthe oily excipient QS 1 ml.

The challenge is carried out on D49, by the oronasal route for an FHVchallenge strain.

The clinical monitoring is carried out for 14 days after challenge,noting the clinical signs (noting of the clinical signs according to therules of the European Pharmacopoeia).

Protection is assessed after challenge on the following criteria:

mean clinical scores for each group, compared with each other and withthe mean clinical score for the control group

level of FHV viral excretion after challenge (measurement of the viralload in pharyngeal swabs prepared daily from D0 to D10 after challenge)

FHV virus neutralizing antibody titres on blood samples collected on D0,D28, D49, D63.

For all these criteria, the mean levels for each group are also comparedwith each other and with the mean level for the control group.

EXAMPLE 13 Application in Dogs

The recombinant virus tested is a recombinant canarypox virus expressingthe HA and F genes of the Carré's disease virus (Canine Distemper Virus,CDV). This recombinant virus is identified vCP258 (see Example 2).

The protocol for vaccination/challenge in the CDV model is thefollowing.

Number of Diluent/ Group dogs Vaccine adjuvant Dose A 6 vCP258 water10^(7.0) pfu B 6 vCP258 Carbopol ® 10^(7.0) pfu 974P C 6 EURICAN ® — 1commercial dose D 6 — — — (controls)

The dogs are vaccinated on D0 and D28 by the subcutaneous route.

The vaccine EURICAN® (CHPPI2) is a live vaccine marketed by Mérial,Lyon, France. One commercial dose contains a minimum of 10⁴ pfu of theCDV Onderstepoort vaccinal strain.

The challenge is made on D56 by intracranial administration of a{fraction (1/10)} dilution of the CDV “Snyder-Hill” challenge strain(batch prepared and provided by USDA). Clinical monitoring is performedfor 21 days after challenge, noting the clinical signs (noting of theclinical signs according to the rules of the European Pharmacopoeia).

Protection is assessed after challenge on the following criteria:

mean clinical scores for each group, compared with each other and withthe mean clinical score of the control group

CDV viraemia level after challenge (measurement of the viral load in thelymphocytes on D56, D61, D63, D66, D70, D77)

CDV virus neutralizing antibody titres on D0, D14, D28, D42, D56, D63,D77.

For all these criteria, the mean levels for each group are also comparedwith each other and with the mean level for the control group.

31 1 1698 DNA Equine Influenza Virus, Newmarket 2/93 Strain 1 atgaagacaaccattatttt gatactactg acccattggg tctacagtca aaacccaacc 60 agtggcaacaacacagccac attatgtctg ggacaccatg cagtagcaaa tggaacattg 120 gtaaaaacaataactgatga ccaaattgag gtgacaaatg ctactgaatt agttcagagc 180 atttcaatagggaaaatatg caacaactca tatagagttc tagatggaag aaattgcaca 240 ttaatagatgcaatgctagg agacccccac tgtgatgtct ttcagtatga gaattgggac 300 ctcttcatagaaagaagcag cgctttcagc aattgctacc catatgacat ccctgactat 360 gcatcgctccggtccattgt agcatcctca ggaacattgg aattcacagc agagggattc 420 acatggacaggtgtcactca aaacggaaga agtggagcct gcaaaagggg atcagccgat 480 agtttctttagccgactgaa ttggctaaca aaatctggaa actcttaccc cacattgaat 540 gtgacaatgcctaacaataa aaatttcgac aaactataca tctgggggat tcatcacccg 600 agctcaaaccaacagcagac agaattgtac atccaagaat caggacgagt aacagtctca 660 acaaaaagaagtcaacaaac gataatccct aatatcggat ctagaccatg ggtcaggggt 720 caatcaggcaggataagcat atactggacc attgtaaaac ctggagatat cctaatgata 780 aacagtaatggcaacttagt tgcaccgcgg ggatatttta aattgaaaac agggaaaagc 840 tctgtaatgagatcagatgc acccatagac atttgtgtgt ctgaatgtat tacaccaaat 900 ggaagcatccccaacgacaa accatttcaa aatgtgaaca aagttacata tggaaaatgc 960 cccaagtatatcaggcaaaa cactttaaag ctggccactg ggatgaggaa tgtaccagaa 1020 aagcaaatcagaggaatctt tggagcaata gcgggattca tagaaaacgg ctgggaagga 1080 atggttgatgggtggtatgg attccgatat caaaactcgg aaggaacagg acaagctgca 1140 gatctaaagagcactcaagc agccatcgac cagattaatg gaaaattaaa cagagtgatt 1200 gaaaggaccaatgagaaatt ccatcaaata gagaaggaat tctcagaagt agaagggaga 1260 atccaggacttggagaagta tgtagaagac accaaaatag acctatggtc ctacaatgca 1320 gaattgctggtggctctaga aaatcaacat acaattgact taacagatgc agaaatgaat 1380 aaattattcgagaagactag acgccagtta agagaaaacg cggaagacat gggaggtgga 1440 tgtttcaagatttaccacaa atgtgataat gcatgcattg gatcaataag aaatgggaca 1500 tatgaccattacatatacag agatgaagca ttaaacaacc gatttcaaat caaaggtgtt 1560 gagttgaaatcaggctacaa agattggata ctgtggattt cattcgccat atcatgcttc 1620 ttaatttgcgttgttctatt gggtctcatt atgtgggctt gccaaaaagg caacatcaga 1680 tgcaacatttgcatttga 1698 2 2956 DNA Feline Herpesvirus 2 atgtatggtt actggctggaatgtgttatt tgtacagtca tatgtaatgt accactcaac 60 acgatatatt tatatcgcggttgtgtctaa taactgtttt taaataaaga gataagtcga 120 aatcacaggc agtgaaatgccttaaaaatg ggtctcctgt ctatgttagg aatctcttat 180 tttaagtagt cccgcgagacgatttacatc ccgggatcac caacaatctg cgatgagacg 240 atataggatg ggacgcggaatctaccttct ctatatctgt ctgttatata catatctcca 300 gtttggtact tcgtcgacaaccgcggtcag tattgaaaat agtgataata gtactgcgga 360 gatgttatca tctaccagcatgtccgctac caccccgata tcccagccaa catctccatt 420 cactactcca actagaagatctacaaatat agctacaagt tcgagtacca cccaggcatc 480 ccagccaaca tctacattaactactctaac tagaagctcg acaactatag ctacaagtcc 540 gagtaccacc caggcagccacattcatagg atcatctacc gattccaata ccactttact 600 caaaacaaca aaaaaaccaaagcgtaaaaa gaataagaat aacggggcca gatttaaatt 660 agattgtgga tataagggggttatctacag accgtatttt agccctcttc agctaaactg 720 tactctaccc acagaacctcatattaccaa ccctattgac ttcgagatct ggtttaaacc 780 acgcaccaga tttggggattttcttgggga taaagaagac ttcgtaggga atcatacccg 840 caccagcata ttactatttagcagccgtaa tgggagtgtt aattccatgg atcttgggga 900 cgcgacactc gggatcctacaatctaggat accagattac acattatata atattcccat 960 acaacatacc gaagcgatgtcattgggaat caaatctgtg gaatctgcca cgtccggtgt 1020 ttatacatgg cgggtctatggtggagatgg actaaataaa acagtgctag gacaggtaaa 1080 tgtatctgta gtggcatatcaccccccgag cgtaaatctt acaccacgcg ccagtctatt 1140 taataagacc tttgaggcggtatgtgcagt ggcgaattac ttcccgcgat ccacgaaact 1200 aacatggtat cttgacgggaagccaataga aaggcaatac atttcagata cggcaagtgt 1260 atggatagat ggactcatcaccagaagttc tgtgttggct attccgacaa ctgaaacaga 1320 ttccgagaaa ccagatatacgatgtgattt ggaatggcat gaaagtcctg tgtcctataa 1380 gagattcacg aaaagtgtagccccggacgt ctattaccca cctactgtgt ctgttacctt 1440 cgctgataca cgggctatatgtgatgttaa atgtgtacca cgggacggga tatccttgat 1500 gtggaaaatt ggtaactaccatctaccaaa agcaatgagt gctgatatac tgatcacagg 1560 tccgtgtata gaacgtccaggtttggtcaa cattcagagt atgtgtgata tatcagaaac 1620 ggatggaccc gtgagttatacctgtcagac catcggatac ccaccaattc taccgggatt 1680 ttacgacaca caagtctacgacgcgtcccc tgaaatcgtc agtgaatcaa tgttggttag 1740 tgtcgttgct gtaatactaggagctgttct catcacagtc tttatcttta ttacggcatt 1800 atgtttatat tattctcatccccggcgatt ataactctta tagttcgtat aaattactta 1860 tcataaccgt gtttcagcggttatattttt ataacagtta attgtttact aatagtttac 1920 aaagtccatc gtttataaaaaacaagccca gtggtattat aatcattcgt atggatataa 1980 accgactcca atccgtgatctttggtaacc cgcgacgtaa ttactctcac acattttaac 2040 tagtctacga tcacccagatataataaaaa gattcgcgtg gacatgcaag gtatgaggtc 2100 tacgtcacag ccgttggtcgagataccact ggtagatatg gaaccacagc catctataca 2160 ctccaacgag cctaacccaccgaataaaat gttgacgaca gctatttcat cgcgtaggag 2220 tggaattttt ttattttctctgggtatgtt ttttttcgga gttatcctaa cagctactat 2280 tatagtatgt acattcatatttacaatacc agtggatatg ctccagatgc cacgctgccc 2340 tgaggaaacg gtgggtatcaaaaactgttg tatccgaccg attagacgcc atgttaaatc 2400 acaccaagat ctagttgccacatgtgccga atacatggaa caacccgccg gccgcatctg 2460 ctgttggagc gcttataccattattggaca tcttcaatgg agatgggata tctacaaacg 2520 actctcttta cgattgtattctctctgatg aaaaaaaatc gtgtaataca tcaatggccg 2580 tatgtcaatc aacatatcttccaaatcccc taagtgactt tattatgcgc gttaggcaga 2640 tattttctgg aatcctaaatcattaatcca tttactaaat aaataaacaa taccgtttag 2700 gtaattaaac atgattctagtgtttattgt cgtatgtacg ggcgatgggt ggataacaac 2760 tcgacaatga tcaattatattgattaacct tgtaataaat tcgtcggatt attggatata 2820 tcgagatgat atcacattattttctaatag cgtgtgtttg aaagtccacc ctactagtgc 2880 catgtgcgcg tttgatcgaagaggcattta atgttgccag agtttcaatt ccgtatgtat 2940 cgtcgagtaa tctaga 29563 70 DNA Equine influenza virus 3 cgcggccatc gcgatatccg ttaagtttgtatcgtaatga acactcaaat tctaatatta 60 gccacttcgg 70 4 36 DNA Equineinfluenza virus 4 cgcgcggcgg taccttatat acaaatagtg caccgc 36 5 70 DNAEquine influenza virus 5 cgcggccatc gcgatatccg ttaagtttgt atcgtaatgaagacaaccat tattttgata 60 ctactgaccc 70 6 42 DNA Equine influenza virus 6cgcgcggcgg tacctcaaat gcaaatgttg catctgatgt tg 42 7 40 DNA Equineinfluenza virus 7 ttgtcgactc aatcatgaag acaaccatta ttttgatact 40 8 34DNA Equine influenza virus 8 ttggatcctt actcaaatgc aaatgttgca yctg 34 974 DNA Equine influenza virus 9 ctagttcgcg atatccgtta agtttgtatcgtaatgaaga caaccattat tttgatacta 60 ctgacccatt gggt 74 10 72 DNA Equineinfluenza virus 10 agacccaatg ggtcagtagt atcaaaataa tggttgtcttcattacgata caaacttaac 60 ggatatcgcg aa 72 11 20 DNA Feline Herpesvirus11 gattaaacct aaataattgt 20 12 42 DNA Feline Herpesvirus 12 tttttctagactgcagcccg ggacatcatg cagtggttaa ac 42 13 18 DNA Feline Herpesvirus 13gggtttcaga ggcagttc 18 14 21 DNA Feline Herpesvirus 14 atgtccactcgtggcgatct t 21 15 42 DNA Feline Herpesvirus 15 tttttctaga ctgcagcccgggacatcatg cagtggttaa ac 42 16 21 DNA Feline Herpesvirus 16 gtggacacatatagaaagtc g 21 17 21 DNA Feline Herpesvirus 17 caccttcagg atctactgtc g21 18 24 DNA Feline Herpesvirus 18 acgcatgatg acaagattat tatc 24 19 18DNA Feline Herpesvirus 19 ctgtggaatt cgcaatgc 18 20 48 DNA FelineHerpesvirus 20 aaaactgcag cccgggaagc ttacaaaaat tagatttgtt tcagtatc 4821 36 DNA Feline Herpesvirus 21 ggtatggcaa atttctttca gggactcggg gatgtg36 22 17 DNA Feline Herpesvirus 22 tttatattgt aattata 17 23 17 DNAFeline Herpesvirus 23 gtaaaacgac ggccagt 17 24 21 DNA Feline Herpesvirus24 atgatgacac gtctacattt t 21 25 21 DNA Feline Herpesvirus 25 tgttacataacgtacttcag c 21 26 18 DNA Feline Herpesvirus 26 gaggattcga aacggtcc 1827 53 DNA Feline Herpesvirus 27 aattttctcg agaagcttgt taacaaaaatcattaaggat ggtagattgc atg 53 28 55 DNA Feline Herpesvirus 28 cattatcgcgatatccgtta agtttgtatc gtaatgagac gatataggat gggac 55 29 18 DNA FelineHerpesvirus 29 actattttca atactgac 18 30 18 DNA Feline Herpesvirus 30aaatgtgtac cacgggac 18 31 54 DNA Feline Herpesvirus 31 aagaagcttctgcagaattc gttaacaaaa atcattataa tcgccgggga tgag 54

What is claimed is:
 1. A vaccine composition against influenza virus inan equine host comprising at least one recombinant virus, selected fromthe group consisting of canarypox virus, fowlpox virus and pigeonpoxvirus, containing and expressing in the equine host at least one nucleicacid molecule encoding at least one heterologous influenza protein; and,as an adjuvant, a polymer having monomeric units of the formula:

in which R₁ and R₂ are identical or different and are H or CH₃; x is 0or 1; y is 1 or 2; and x+y=2.
 2. A vaccine composition against influenzavirus in an equine host comprising at least one recombinant virus,selected from the group consisting of canarypox virus, fowlpox virus andpigeonpox virus, containing and expressing at least one nucleic acidmolecule encoding at least one heterologous influenza protein; and, asan adjuvant, a polymer of acrylic or methacrylic acid.
 3. The vaccinecomposition of claim 2 wherein the adjuvant is a polymer of acrylicacid.
 4. The vaccine composition of claim 2 wherein the adjuvant is apolymer of methacrylic acid.
 5. The vaccine composition of claim 2wherein the adjuvant is a cross-linked polymer of acrylic acid.
 6. Thevaccine composition of claim 5 wherein the adjuvant is a carbomer. 7.The vaccine composition of claim 5 wherein the adjuvant is a polymer ofacrylic acid cross-linked with allyl sucrose or with allylpentaerythitol.
 8. The vaccine composition of claim 2 wherein therecombinant virus is a recombinant canarypox virus.
 9. The vaccinecomposition of claim 2 wherein the recombinant virus is a recombinantfowlpox virus.
 10. The vaccine composition of claim 2 wherein therecombinant virus is a recombinant pigeonpox virus.
 11. The vaccinecomposition of claim 1 or 2 wherein the adjuvant is present in an amountof 0.01% to 2% w/v.
 12. The vaccine composition of claim 11 wherein theadjuvant is present in an amount of 0.06 to 1% w/v.
 13. The vaccinecomposition of claim 11 wherein the adjuvant is present in an amount of0.1 to 0.6% w/v.
 14. The vaccine composition of claim 1 or 2 wherein theequine influenza protein comprises equine influenza HA protein.
 15. Thevaccine composition of claim 14 wherein the recombinant virus is acanarypox virus.
 16. The vaccine composition of claim 1 or 2 whichcomprises two or three recombinant canarypox viruses, each of whichcontains a nucleic acid molecule that encodes, and each of whichexpresses, an influenza HA protein from a different influenza strain.17. The vaccine composition of claim 1 or 2 which comprises arecombinant canarypox virus that contains nucleic acid molecules thatencode, and that expresses, two or three different influenza HAproteins, each of which is from a different strain of influenza virus.18. A method for vaccinating an equine against influenza comprisingadministering to the equine the vaccine composition as claimed in anyone of claims 1-17, in an amount effective for vaccination.
 19. A methodfor preparing the vaccine composition as claimed in claim 1 or 2comprising admixing the recombinant virus and the adjuvant.
 20. A kitfor preparing the vaccine composition of claim 1 or 2 comprising a firstcontainer containing the recombinant virus and a second containercontaining the adjuvant.
 21. The kit of claim 20 wherein the recombinantvirus is in freeze-dried form.
 22. The vaccine composition of claim 1 or2, wherein the influenza virus is equine influenza virus.
 23. Animmunogenic composition against influenza virus in an equine hostcomprising at least one recombinant virus, selected from the groupconsisting of canarypox virus, fowlpox virus and pigeonpox virus,containing and expressing in the equine host at least one nucleic acidmolecule encoding at least one heterologous influenza protein; and, asan adjuvant, a polymer having monomeric units of the formula:

in which R₁ and R₂ are identical or different and are H or CH₃; x is 0or 1; y is 1 or 2; and x+y=2.
 24. An immunogenic composition againstinfluenza virus in an equine host comprising at least one recombinantvirus, selected from the group consisting of canarypox virus, fowlpoxvirus and pigeonpox virus, containing and expressing at least onenucleic acid molecule encoding at least one heterologous influenzaprotein; and, as an adjuvant, a polymer of acrylic or methacrylic acid.25. The immunogenic composition of claim 24 wherein the adjuvant is apolymer of methacrylic acid.
 26. The immunogenic composition of claim 24wherein the adjuvant is a polymer of acrylic acid.
 27. The immunogeniccomposition of claim 24 wherein the adjuvant is a cross-linked polymerof acrylic acid.
 28. The immunogenic composition of claim 27 wherein theadjuvant is a carbomer.
 29. The immunogenic composition of claim 27wherein the adjuvant is a polymer of acrylic acid cross-linked withallyl sucrose or with allyl pentaerythitol.
 30. The immunogeniccomposition of claim 23 or 24 wherein the recombinant virus is arecombinant canarypox virus.
 31. The immunogenic composition of claim 24wherein the recombinant virus is a recombinant fowlpox virus.
 32. Theimmunogenic composition of claim 24 wherein the recombinant virus is arecombinant pigeonpox virus.
 33. The immunogenic composition of claim 23or 24 wherein the adjuvant is present in an amount of 0.01% to 2% w/v.34. The immunogenic composition of claim 33 wherein the adjuvant ispresent in an amount of 0.06 to 1% w/v.
 35. The immunogenic compositionof claim 33 wherein the adjuvant is present in an amount of 0.1 to 0.6%w/v.
 36. The immunogenic composition of claim 23 or 24 wherein theinfluenza protein comprises influenza HA protein.
 37. The immunogeniccomposition of claim 36 wherein the recombinant virus is a canarypoxvirus.
 38. The immunogenic composition of claim 23 or 24 which comprisestwo or three recombinant canarypox viruses, each of which contains anucleic acid molecule that encodes, and each of which expresses, aninfluenza HA protein from a different influenza strain.
 39. Theimmunogenic composition of claim 23 or 24 which comprises a recombinantcanarypox virus that contains nucleic acid molecules that encode, aridthat expresses, two or three different influenza HA proteins, each ofwhich is from a different strain of influenza virus.
 40. A method forinducing in an equine an immunological response against influenzacomprising administering to the equine the immunogenic composition ofany one of claims 24-39, in an amount effective for inducing theimmunological response.
 41. A method for preparing the immunogeniccomposition of claim 23 or 24 comprising admixing the recombinant virusand the adjuvant.
 42. A kit for preparing the immunogenic composition ofclaim 23 or 24 comprising a first container containing the recombinantvirus and a second container containing the adjuvant.
 43. The kit ofclaim 42 wherein the recombinant virus is in freeze-dried form.
 44. Theimmunogenic composition of claim 23 or 24, wherein the influenza isequine influenza virus.
 45. A vaccine composition against influenzavirus in an equine host comprising: a) at least one recombinant virus,selected from the group consisting of canarypox virus, fowlpox virus andpigeonpox virus, containing and expressing in the equine host, a nucleicacid molecule encoding influenza A2 HA; and b) a carbomer; wherein thevaccine composition, when injected into Welsh Mountain ponies notpreviously infected by influenza, as a 4 mg/ml carbomer compositioncontaining 10^(7.7)TCID₅₀ recombinant virus, achieves at day 14 afterinjection a mean antibody titre against influenza HA of 155.4±32.9, asmeasured by single radial hemolysis (SRH).
 46. The vaccine of claim 45,wherein the recombinant virus is a canarypox virus.
 47. The vaccine ofclaim 46, wherein the canarypox virus is ALVAC.
 48. The vaccine of claim45, wherein the recombinant virus is a fowlpox virus.
 49. The vaccine ofclaim 45, wherein the recombinant virus is a pigeonpox virus.